In a yarn feeding device which is known from WO 92/22693 (U.S. Pat. No. 5,094,275), a pneumatic valve device which consists either of a main switching valve with inhibiting valves arranged downstream thereof, or of a multi-position multi-way valve or of a rotary slide valve, serves to selectively actuate either only one yarn threading nozzle provided at the feed side or to actuate a plurality of yarn feeding nozzles with compressed air.
In a yarn feeding device which is known from the brochure "Galaxy", reference number 48-1025-201/9239, of the company IRO AB, SE, page 15, issued in 1992, a pneumatic valve device is installed in the motor housing which can selectively be operated by means of two valve openers that are formed as externally accessible push buttons, namely in such a manner that either only the threading nozzle at the feed side is pressurized (by pressing the push button arranged on the back side of the motor housing) or all of the threading nozzles are pressurized (by pressing the push button arranged at the side of the motor housing). In these yarn feeding devices, which have been on the market since 1992, the valve device comprises a metal block in which two valves that are selectively actuable by means of the valve openers are contained in a chamber which is connected to a source of pressure and from which flow channels lead to the yarn threading nozzle at the feed side and to the other yam threading nozzles. In addition, a transverse connection is provided between the flow channels in the housing, the transverse connection containing a check valve which automatically opens in the flow direction towards the threading nozzle at the feed side, and automatically shuts off in the opposite flow direction. The valve device with the valve openers is composed of many parts and is technically troublesome with respect to manufacture and mounting.
In a yarn feeding device which is known from U.S. Pat. No. 5,181,544, a block which is connected to the motor housing has provided therein a compressed-air distributor which leads to a plurality of threading nozzles and to a pneumatic piston-cylinder unit and has arranged upstream thereof a valve which can be actuated by means of a valve opener. However, it is only possible to pressurize all of the consumers at the same time.
Finally, EP-A-0 418 949 discloses a valve device comprising a block-shaped housing and two valves, with two push buttons being provided for selectively connecting one of two outlets or both outlets to the source of pressure. To connect both outlets to the source of pressure, both push buttons must be pressed.
It is the object of the present invention to provide a valve device of the above-mentioned type and a yarn feeding device comprising such a valve device, in the case of which it is possible to choose between an individual actuation and the multiple actuation of consumers in a simple manner with respect to production and also in a user-friendly way.